Hopefully there's at least one other Crawlbot owner here who might be able to help me... I've set up my Crawlbot and am trying to cut the PB logo test, but I'm running into issues. The Crawlbot cuts the first hole in three passes, but when it moves to cut the second hole the router isn't lifting up at all, so it's cutting through the plywood (all 3/4" of it) in one pass, when it's not supposed to be cutting at all. Then it moves on to cut the logo, still without retracting at all.

I've followed the setup instructions, lowered the router down until the bit makes contact with the work surface, zeroed all axis, then run the sample gcode.

If anyone has any suggestions I'd greatly appreciate it. I've tried numerous times now with the same results.

Crawlbot Test Cut Issue

Does your gcode sender let you preview the cutting? Does your Z move up and down as you expect otherwise (your sender or control program should have manual axis moves)? If so, the sample gcode is likely missing the move to safe height between the two cutouts. Otherwise your Z isn't moving up (look for loose couplings, etc) when the controller tries to do so. If you're cutting in multiple passes as you expect it can stay in position and move down when commanded, so I'd suspect that it can't lift the router weight. What happens if you remove the workpiece, raise the Z a bit, leave the router turned off and run the gcode (it's called air cutting, leaving the router off makes it a lot quieter)? When it moved to the second letter without raising does it continue to lower with each layer of the cut, or does it move down (into your spoilboard if you're not quick) when it does the other letter? Can you hear missed steps when it tries to bring the router up, assuming it does in the appropriate places?

I use(d) LinuxCNC on a different manufacturer's CNC router (plus a Gecko G540 controller), but the basic process should be the same for any gcode controlled device. There's some other non-PB CNCers here, too.

Not to be obvious, did you try contacting Printrbot (we're independent, not part of the PBien empire)? Unrelated to this, but you should go check out the forums at cnczone.com , too.

Previewing it in CAMotics, I do see the tool being raised between moves. I am able to raise and lower the tool through the Printrbot control software, so there doesn't seem to be an issue with movement.

I'll try running it without the tool this evening and see if there's any difference, but I'm not expecting there to be. I'm rather stumped at this point as it seems everything should be working as expected.

So it turns out this was nothing wrong with the machine and nothing wrong with what I was doing. After trying it again a couple times with the Printrbot control software, I decided to try it in ChiliPeppr. It turns out ChiliPeppr worked perfectly fine and cut the Printrbot logo sample as expected.